Deletion of 5q31 and 7q31 in patients with stable melphalan treated multiple myeloma

5q- syndrome and multiple myeloma diagnosed simultaneously and successful treated with lenalidomide

A 72-year-old woman was diagnosed with 5q- myelodysplastic syndrome in the course of an indolent multiple myeloma (MM). Bone marrow (BM) cytogenetics disclosed two unrelated clones: 46,XX,del(5)(q13q33), and [47,X,-X,der(1;21)(q10;q10),-4,-4,+5,del(5)(q13q31),+7,der(7)t(1;7)(p34.2;p22),add(8)(p23),-13,+15,der(16) t(1;16)(q23;q12.2),+19,-21,+mar1,+mar2]. The last complex karyotype belonged to malignant plasma cells. FISH and SKY techniques demonstrated different 5q deletions. EGR1 gene (on 5q31) lost in 5q- syndrome remained in 5q- plasma cells. Biclonal evolution was noted: myeloid 5q- cells added a deletion 13q and plasma cells showed monosomy 13. Patient achieved complete cytogenetic response of 5q- syndrome with low-dose of lenalidomide, and a partial remission of MM with high-dose of lenalidomide/dexamethasone combination.

Longitudinal bone marrow evaluations for myelodysplasia in patients with myeloma before and after treatment with lenalidomide

Lenalidomide (LEN) treatment in multiple myeloma (MM) results in a superior outcome. However, there is concern for increased myelodysplastic syndrome/acute myeloid leukemia (MDS/AML) associated with LEN. Thus, bone marrow morphology and cytogenetics studies from 40 patients were evaluated for early signs of MDS prior to therapy, during therapy and at follow-up. Newly diagnosed patients with MM treated with LEN and dexamethasone (LD) alone or followed by autologous stem cell transplant (LD/ASCT), or patients with relapsed/refractory MM treated with LEN, bendamustine and dexamethasone (BLD) were included. One patient developed MDS. Baseline prevalence of mild morphologic myelodysplasia was highest in pretreated patients with MM (BLD, 71%), but was also seen in newly diagnosed patients (LD and LD/ASCT, 17%). The prevalence of myelodysplasia did not increase over time. Thus, this study did not reveal rapidly emerging MDS in 39 of 40 patients with MM treated with LEN. The development of MDS in one patient suggests that longer follow-up is needed for all.

Derivative (1;7)(q10;p10) in multiple myeloma. A sign of therapy-related hidden myelodysplastic syndrome

Therapy-related myelodysplastic syndrome (MDS) is a major problem in long-term cancer survivors, therefore early detection and prevention of therapy-related secondary neoplasia is an important issue. We searched for therapy-related MDS and analyzed cytogenetic changes in 155 patients with multiple myeloma (MM) from a single institution. Of the total 155 MM patients with cytogenetic results, 7 patients showed de novo appearance of myeloid-related cytogenetic changes, and 5/7 had -7/7q-, including 3 with der(1;7)(q10;p10): 3 patients developed MDS (i.e. 2 patients with der(1;7)(q10;p10) and 1 with a complex abnormality including -5 and 7q-). Among five patients receiving more than 2 g of melphalan, three developed MDS, and two of them showed der(1;7)(q10;p10) before or at the time of MDS diagnosis. Although morphologic identification of MDS was difficult in some cases, we concluded that the presence of 7q-, specifically der(1;7)(q10;p10), during chemotherapy involving melphalan for MM patients might indicate hidden MDS status and appropriate therapeutic options should be considered for such patients.

Use of chromosome painting for detecting stable chromosome aberrations induced by melphalan in mice

Chromosomal aberrations are a measure of genomic instability, which is known to play a key role in the initiation and promotion of carcinogenesis. Stable reciprocal translocations are of particular importance since they are often involved in neoplastic transformation and tumor cell clonal evolution. In this study, chromosome painting analysis was used to test for stable aberrations induced in the bone marrow of C57BL/6J and FVB mice exposed for 4 weeks to 2 or 4 mg/kg of melphalan (MLP), a chemotherapeutic agent with carcinogenic potential. To compare the chemical-induced damage in different tissues, chromosome aberrations were also analyzed by chromosome painting in the spleen of C57BL/6J mice. At the 2 mg/kg dose, MLP induced comparable levels of chromosome-type aberrations in bone marrow cells of both mouse strains and in splenocytes of C57BL/6J mice. At 4 mg/kg, no further increase in aberrations was detected in bone marrow, while a dose-effect relationship was found in spleen cells. This different response may result from a negative selection against highly damaged bone marrow cells during mitotic proliferation. The results indicate that chromosome painting is a useful tool for detecting stable chromosome aberrations in somatic cells exposed to MLP and possibly to other genotoxic chemical carcinogens.